﻿using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Windows.Data;

namespace Slex.Lib.Interactions
{
    /// <summary>
    /// A trigger to fire when a property changes
    /// </summary>
    public class PropertyTrigger 
        :   EventBasedTrigger 
    {

        #region Public Properties

        /// <summary>
        /// Name of the property to listen
        /// </summary>
        public string Property
        {
            get { return (string)GetValue(PropertyProperty); }
            set { SetValue(PropertyProperty, value); }
        }

        // Using a DependencyProperty as the backing store for Property.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty PropertyProperty =
            DependencyProperty.Register("Property", typeof(string), typeof(PropertyTrigger), new PropertyMetadata(null,OnParameterChanged));


        #endregion


        /// <summary>
        /// Callback to re-initialize our trigger bindings
        /// </summary>
        /// <param name="d"></param>
        /// <param name="e"></param>
        public static void OnParameterChanged
                (DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
           //Future plans
        }

      

        /// <summary>
        /// Callback invoked when the property changes
        /// </summary>
        /// <param name="dependencyObject"></param>
        /// <param name="eventArgs"></param>
        private void OnListenAttachedPropertyChanged(System.Windows.DependencyObject dependencyObject,
            System.Windows.DependencyPropertyChangedEventArgs eventArgs)
        {
            if (initialized)
            {
                var e=new EventResult() { Sender = dependencyObject, Args = eventArgs };
                this.InvokeConditional(e);
            }
        }


        /// <summary>
        /// Does the initialization
        /// </summary>
        protected override void Initialize()
        {
            if (Source == null)
                throw new InvalidOperationException("Source specified for this trigger is null");
            if (string.IsNullOrEmpty(Property))
                throw new InvalidOperationException("PropertyPath specified for this trigger is null or empty");

            this.RegisterForNotification(Source,
                Property, OnListenAttachedPropertyChanged);
        }
    }
   
}
